In general, this invention relates to package lift devices useful in yarn winding apparatus. Specifically, the lift device disclosed herein is particularly useful in connection with the individual yarn winding stations associated with the spinning stations of an open-end spinning machine.
In a typical yarn winding apparatus, a yarn package is held by a package support device in a manner to permit rotation of the package. During winding, the package is held in contact with a rotating package drive roll which in turn causes the package to rotate. In many cases the package support device comprises a pair of parallel support arms which hold the yarn package between them and are pivotally mounted at a point displaced from the yarn package to facilitate raising the package off of the drive roll as necessary. This construction also permits normal movement of the package support as the package becomes larger during the spinning operation.
At times it is desirable to automatically lift the yarn package off of the drive roll when a particular condition exists. For example, if the yarn package remains in contact with the drive roll when a break occurs in the yarn being wound, the broken end becomes entangled in the windings of the package. When this occurs the broken ends must be joined together (pieced-up) so that the winding operation may continue. In order to readily accomplish the piecing-up operation, it is desirable that the broken end associated with the yarn package be easily located. Thus, it is necessary to provide a device which will automatically lift the yarn package off of the drive roll when a yarn break occurs thereby avoiding entanglement in the package.
Once the condition which necessitated lifting the package has been corrected, it is necessary to deactivate the lift mechanism to permit the package to be lowered into contact with the drive roll so that winding may continue. In certain types of textile machines, space limitations result in the need for a simple means of deactivating the lift device which does not depend on manual operation or complex apparatus. For example, in modern open-end spinning machines the spinning stations and corresponding winding stations are very close together and manual resetting of the lift mechanism is difficult. Further, in an open-end spinning machine utilizing automatic piece-up devices, it is necessary to provide a lift mechanism which automatically resets itself as the piece-up operation is concluded.
The invention disclosed herein addresses these problems by providing a simple lift device which automatically lifts a package in response to a sensed condition and resets itself to permit lowering of the package into contact with the drive roll.